Since the earliest of modern times, it has been recognized as desirable to provide a cost-effective means for producing useful, practical illumination from electrical energy. Most inhabitants of modern countries are familiar with various lighting means including incandescent lamps and arc discharge or fluorescent lighting. It is to the art of arc discharge lamps to which the present invention is concerned, to the extent that it is desirable to provide a cost-effective means for retrofitting existing electrical devices which employ incandescent lamps to the use of fluorescent lamps.
The art of arc discharge lamps took a quantum leap with the successful demonstration of the usefulness of these lamps by Charles F. Brush in his March 1880 demonstration in the town of Wabash, Indiana. Mr. Brush's lamps comprised carbon electrodes sealed in a chamber in vacuo along with a prescribed quantity of elemental sodium. The electrons of monatomic sodium vapor contained in the envelope absorb energy and undergo a transition, emitting photons visible as the yellow light frequently observed by passers-by along various highways today. Arc-discharge lamps are generally more desirable than their incandescent counterparts since they produce a relatively large amount of lumens per energy input and dissipate a lessened amount of energy in the form of heat as compared with incandescent lamps. However, the discharge lamps typically require an increased amount of associated hardware relative to incandescent lamps. Accordingly, arc-discharge lamps have only found use where the energy savings can offset the costs of the additional hardwares required. Nevertheless, ever since the initial efforts of Mr. Brush, it has been an ongoing goal of pioneers in the lighting industries to devise such contrivances as may have been believed to render arc-lighting more economically affordable to a larger number of consumers, for various reasons.
Accordingly, the prior art is replete with examples of developments related to reaping the advantages associated with arc lighting. Many of these developments are concerned with the retrofit or use of existing electrical systems which were originally designed for use with incandescent lamps to arc discharge lamp uses. For example, U.S. Pat. No. 5,634,820 describes an adapter module which allows the use of a low-wattage, compact fluorescent lamp in an ordinary light socket. The lamp has a built-in ballast, and the unit as a whole is discarded upon lamp failure; U.S. Pat. No. 5,596,247 describes a fluorescent lamp which is designed to screw into an existing light socket; U.S. Pat. No. 5,135,407 describes a conversion kit which enables the user of a portable work light to substitute a fluorescent lamp in the place of an incandescent lamp; U.S. Pat. No. 5,073,845 describes a retrofit socket useful with fluorescent light fixtures; U.S. Pat. No. 4,936,789 teaches an assembly through which an incandescent lamp may be powered from a standard incandescent lamp socket; and U.S. Pat. No. 4,723,200 teaches a holder for an electric light, all of which, including patents cited as references therein are herein incorporated by reference. However, each of the teachings of the prior art are not without one or more inherent disadvantages rendering them unsuitable for providing en masse adoption of the use of fluorescent lamps in various capacities formerly reserved for incandescent lighting.
Generally speaking, compact arc-discharge lamps or compact fluorescent lamps (CFL's) have power ratings in the range of about 5-50 watts and vary in size accordingly. These fluorescent lamps are not directly interchangeable with the incandescent lamps they are intended to replace owing to the different operating requirements of each. One of the extra items required in an arc lighting system a ballast, which consists essentially of a coil of wire of many turns and which functions to limit the flow of current through the lamp which, in the absence of the ballast would otherwise be practically limitless, thus destroying the fluorescent tube in short order. Therefore, fluorescent lamps have specially designed bases which ensure that they are not inserted into lamp sockets intended for the incandescent. Built-in ballasts are common in fluorescent lamps for wattages up to about 20 W. However, such systems are uneconomical in that when the CFL lamp eventually fails the unit as a whole, including the ballast, must be discarded. For the fluorescent lamps available which contain internal ballasts, the ability to include the ballast in the lamps is limited by the wattage of the lamp. For example, it is not practicable to provide internal ballasts on lamps having wattages greater than about 20 W. Through use of the instant invention, there is no limit to the wattage of the lamp retrofitted. Additionally, it is not necessary to discard the ballast when the lamp fails, as is required by the prior art lamps which contain an internal ballast; hence use of the instant invention saves end user costs and manufacturing resources. Furthermore, in general terms, the present systems possess the drawbacks that: 1) the increase in lamp wattages desired for a particular use are accompanied by a pendant increase in the size of the ballast required; and 2) many of the newer lamps are incompatible with 120 VAC house current and therefore require that special fixtures or lamp/ballast assemblies must be used.
In consideration of the problems above, it would be desirable to have at hand a device or system which provides a means for permitting existing fixtures comprising incandescent lamps to be readily refitted with fluorescent lamps. It is also desirable to provide a means for providing the possibility of the use of a wide range of ballasts in such systems, including those ballasts with normal power factors, high power factors, magnetic, and electronic types. It would also be desirable to provide such a system which is useful with either two-pin type or four-pin type fluorescent lamps. Since higher wattage arc discharge lamps require larger and more complicated ballasts which will not fit existing fixtures, it would also be desirable to have at hand a means for permitting existing incandescent lamp retrofits for use with fluorescent lamps which permit the easy and convenient interchange of different ballasts, external from the adapter or fixture with coordinated connectors for different lamp types. It would also be desirable that such a device comprise a ballast which is remote with respect to the remaining elements of the device. It would also be desirable for such a system to not require the discard of the ballast along with lamp replacement as is common in the present state of this art. Additionally, it is desirable to provide the possibility of the use of a remote dimming ballast to enable the user to control the intensity of the light emitted by the fluorescent lamp.
Also, owing to the inherent design of the circuitry of the instant invention, it is not possible for the lamp to operate in the situation where there is no ballast connected to the adapter. This is of particular advantage in disallowing an unintentional blowout as is readily possible with the devices of the prior art.
The versatility of the instant invention becomes evident when one considers the fact that with low wattage compact fluorescent lamps having their ballast built in, inexpensive electronics are used. However, with the two-pin compact fluorescent lamps a magnetic ballast must be used because the high voltage kick putout by the glo-bottle starter built into the lamp would destroy the electronics. These lamps will operate on common house current (120 VAC). The compact fluorescent lamps having wattages in the range of about 26-42 W will not operate with 120 VAC because the arc tube voltage is greater than 120V and the lamp would not stay lit. A higher lamp voltage must be supplied by the ballast which is the reason why these ballasts are larger, more expensive, and normally separate from the lamp. Also, such higher wattage lamps are of the 4-pin design. By keeping the ballast separate from the lamp it is possible to install any type ballast and control circuit desired. In the teachings of the prior art, none contains any provision for readily changing the ballast to suit the intended application as provided herein. Through use of this invention it is possible to convert to any arc-discharge lamp instead of an incandescent lamp by merely selecting the proper ballast and inserting the desired arc-lamp socket into the adapter herein. Finally, any household floor or table lamp can be adapted to use fluorescent lamps in accordance with the teachings herein. While the prior art has attempted to permit the same, the devices therein taught are much too large or cumbersome to be used in such applications, since the prior art devices are not suited to fit within existing lamp-shade support harps. Through use of the teachings of the instant invention, it is possible to easily convert any existing lamp socket to a 42 watt compact fluorescent lamp, which emits roughly the same number of lumens as emitted by a 250 W incandescent lamp.